关键词: NDVI, 重心迁移, 时空变化, 地形因子, 气象因子, 生态工程, 西双版纳

Abstract: Based on the MOD13Q1 data synthesized by Moderate Resolution Imaging Spectroradiometer (MODIS), the variation characteristics of Normalized Difference Vegetation Index (NDVI) in Xishuangbanna, Yunan Province before (2004～2010) and after (2011～2017) the implementation of ecological project were analyzed from four aspects of time variation, spatial variation, spatial migration of centroid and terrain factor, and the relationship between NDVI and meteorological factors in summer was discussed. The results showed that (1) NDVI decreased at the rate of -0.176% per year during 2004～2010, while NDVI increased at the rate of 0.221% per year during 2011～2017. (2) The NDVI frequency was featured by a unimodal structure. After the implementation of ecological project, the area of NDVI that is in range of 0.9 to maximum significantly increased by 17.2%, and the centroid of NDVI shifted from the southwest (7.58km migration distance) to the southeast (4.75km migration distance). (3) Compared with NDVI in the years of 2004-2010, NDVI in the years of 2011～2017 increased significantly at an altitude of 720-870m, slopes of 13°-16° and the northeast direction, with the growth rate of 2.7%, 1.4% and 1.2%, respectively. (4) The main factors leading to the lowest NDVI value in summer included high temperature, excessive precipitation and less sunshine duration. (5) The implementation of ecological project had an important impact on the increase of NDVI during 2011～2017, but there was a large proportion of areas showing a NDVI decline, and the ecological environment construction in some areas need to be strengthened.

Key words: NDVI, spatial migration of centroid, temporal and spatial variations, terrain factors, meteorological factors, ecological project, Xishuangbanna